Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c6b8079d6786c67a6c9d18de37e47a636bae97235066a85e413dfea76d4c9a35' 
  AND token = '3tWl3XuxaaqaFwoqxOnYQlvqDWYhgmEp5zDD/CltkNI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}