SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f0be0a73f05287c35785980ce31aadc282c587ef54da28961ae6d85c5f1da95' 
  AND token = 'ke2/r6l5FiPmdvoCitCDX6XQT40p3WGDkUA77eBvHy8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}