SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd3d02faef0d6921cb31f4c9f6bd2f3e77a92855126d9c481487fb86e52df35d' 
  AND token = '/7YhukPMoE5GG9nFgGinVBO3G3PLEjnQB1b6Imtviwc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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