SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1087b2d6739d18c7c3fd22f8471519aa0224cf0d791c4ccf7be254909d55f96d' 
  AND token = 'jKTn+waZXu8Vey0hkej1jBJCBVJMEgXkklYO7XRLJX4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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