SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b72f64539c92d43e8bbb91a9924dcc210d25ebbd431bcd599e6ace22f4cac3a5' 
  AND token = 'b/FyJEEftygDvG1urwHFDl0X/UWqHNQIyH7ifwWoobE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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