SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5776d6e6fab7afc7b47519231a0b05ec1fcae1804e737d824f18c5c4ced29fa1' 
  AND token = 'ENWanEkMwS3JNtdazwM+F1BKu9qlfZG8xvza9xL0vOE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}