SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4d956f22977484606f7aa3ca76e49da398338a2526f2f4f995ca0fb52156926f' 
  AND token = 'KqpzsQI9qN//aSucaczvOzm2ozJJBJ/8JEdX3jH0Zp4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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