SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'a05f5c628008621667943059e9c50ffb97b63dc8db60b658ed7f114a2fd670a6' 
  AND token = '/JKn5Cfo5VyQ+15TRakM84RMrKF6Ox0yyjcWMZBpWgE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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