SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '77ae15b7548eb64797110a75770d3384d984716551bfe2309ba89684ea4ebd43' 
  AND token = 'wuwYU3oWFxph0foGClwaI3pdDGvT9KiPIRf351MO+WM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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