SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3cef3dc97513ba0aee374d3a32c444a2faed0a3ecfd12d9aa625a6d6af4b215f' 
  AND token = 'yA0c28yYasd0t0xm0eL6C/Fco1eo3R/Gc9lKBsWE5m8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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