SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '309a2c9cb003ba78d6e529307be339eaad45ce822c51b995dcfb7383218de730' 
  AND token = 'xA/x0wbk8arHaNSocyYd5M4/myXuguT3YM5wDUsDhwE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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