SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '640fe13f03a65c150c7a227fcc72945bf191af00033862f7e2ec53389c4b4ba7' 
  AND token = 'glWqN152NxVHcR92GAuWE07Gpmga3tKJjhynaz/gS0g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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