SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92762d515afb02cb9471aa3231cf22d681ade54ca8239932baef7e1b71b880ec' 
  AND token = 'W3baZGmrZulHuvqAhPkYe5gHUXSXiU5cDfBPLnMy9wY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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