SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'caf50dad4962cf5100c820ce1989a08b011faaee8abe685fdd3686ed06e48d0f' 
  AND token = 'BVjW0ypxO9uJkeFxpjC2z2GXxyUa8VqsPaGloiQXA7s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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