SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1b048c02aaa115236c369193d4da78a8ee67fe877217a014b8a65d8ed5e6a42d' 
  AND token = 'MrgvXmfMmtZItNIkQjnvLqC/hqTlV7mzKqzaldpib+8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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