SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1b631539097924aaeb55b82a78501ca45529e0cd6aa4e523fc23d047869ec3f7' 
  AND token = 'gLgh9/2w++G8D6G6KKbw/DQY8l0HSVvX6HGFG6NGe04=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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