SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3526c6f24e1c395acf78639cfedc9acd2623ce399f2279637dae075db098d30a' 
  AND token = 'FPxtDd5J1uK/lhrfkTOmqUoigpr0NpHrQQm1cykmz2w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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