SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd705c092cd41c98022be07249832ae3c77adcca374f4d0ca764fd2b5dac73b00' 
  AND token = 'kz7Pqs/WCYDrAr/rZCB1az4/rX1AE7+7CvPyFHLA0XM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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