SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '774e7d785cfcde41edff128d48390a9ff7448ac29c4739a963dc0201add117bd' 
  AND token = '8MoiAAtjCSSVCWZQePniUREz+zbdX3K3J79Fc23Epfc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

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