SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '188d1a954a7b97e20b7213afb9ac78ded952d972d10aa470cd3527d567b6bd86' 
  AND token = 'vPiBK77KXmwj2pFtkUvm2ZOUVQbIgfQTpV7/jUpZsDk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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