SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '106c606351b13b18b770652907fd4597f675039be595df2be14d9a3dd662db04' 
  AND token = 'VJr8Lwdbj3jwT23MxTxV/x+GmVUBpXPQ6XsjGmfCqRc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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