SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '02d7c8f97c13120b76b523fa7be9327577e1f679767794cbcca346a3d0de9b2c' 
  AND token = 'AkWRU3OzqkbnO8ZpkD1Zi6F+RQt+lah96YnBwGunV/Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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