SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0a74d849d02aa6bbbcbf8d07dee98d324f81d9f54484c5ab81d805c520904df6' 
  AND token = 'GVXaUWFX54JOwhnUHFZd3hxw25VHTxsyeO+xzVZTUM4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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