SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ba8af2777847fb7a6a0ee92242f479a41eb7ad0ca4d7d5608e35e54afabe52d' 
  AND token = 'ElD6OEzvf0IyYaHAijd0+t0hGhMSLJsXti0ML95vuvs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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