SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb3ff9be157d6474df2e9379913a6552f168353235e1f3f1101fd67c4c7e1a24' 
  AND token = 'gTbTmKVWo3yKlFnniqxXjOJWKDxIEuKOLe0R0PGYhPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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