SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e35ad27cc20c14bf278e765d3e3028f997680499de43c7bf99c1c03d78135be3' 
  AND token = 'ZPOrIskUlHmJg4CCIxUHRMgJ/1CGfcsI9qmxYA3/L+w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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