SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93299dc0a133d9ca4cd6b682583f518bae1d1e6be69e7c2befd8714201acb3c9' 
  AND token = 'VHnFtPQLBcSFKdLgc/hZ+Yr8W9vuVYczAEqr90IWZlA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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