SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1587aca4414b8c6d0a4d1bf158bfdd153428e688927db4f0908acef6c3857945' 
  AND token = 'cRQIVVow402/Jyxszs5auH/cDqSTntkMqWO1WaLsEn4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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