SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '441e6ac6f005e8a70ebe363f2bcf87259bada1f13df32c8e7295fbe29acbb547' 
  AND token = 'GOsPNr/uZXitlEsZV3kgQhcuYAq9CxpROBWbo20J7Wk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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