SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f7526b51139a4638a95de31ddbbbe2fc2acb929c22d7759bcaf1b0d8d7f0092' 
  AND token = 'XK1Z41e/AMovZWHYpGwYt53SH6uZU7uI2yRpod9bsYc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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