SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b34ee119b4ae93f64d2dfc6878c37d31b654dd1f1d9ec411590a53a1e2f321b2' 
  AND token = 'liJQg4Tk3TTcWVOltZp0VB4/I9ZBjuJZFQW2Y8we88U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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