SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4ff0414a43bdb4b22ba9d3f369ee16200f32028b397f5d03df7af7e9afee089' 
  AND token = 'wuGio058s78qd1NZkmNCoe9X6pS5+fQ+AptoK2IGr9g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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