SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ddbb3593811fb655f9b319e4dfc5545bf473da38df23744e1abad8cbbab8943f' 
  AND token = 'vHK1ySmWkfBzXyDEZt4DVpT2AaA2HYyZL5RogMYUWkA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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