SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '88e369a7c5f5ac8c03e5f45a5bec6530265fe38ba4b642bdeb82bfdebf4263ed' 
  AND token = 'JoaLGJKl3FwfZbLdquCO2n/daBLhJtNbgBtFtQHJpbM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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