SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e8e9ea79c8b42aa45e4de6c675e8f6bfba7bc0b4702ca03ee3cb29d5a7036fff' 
  AND token = 'a0FSAFu52QRo7gROaQR//3TVNEPXySolqHOCWmlbHtg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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