SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45834c5c4b35f3ceba31b7522a051faa2f42ad010951244ffc2eed46682b64ee' 
  AND token = 'VHtgUIlolsPYXHqVUI9n78OadghwjLXLx00umUZF+wc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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