SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f02f47f67b9b9072bc37e823b0879321bce700ea6d99dbc84ba9fc59f591995' 
  AND token = 'JcPGnyZTl5d2lcfDwmLvU0kTIq6DEsVO0/GmDNe5KB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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