SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34d58c766113572f606b920b9f5ca258ac378d27c86dda6acbde1eecd0a61da7' 
  AND token = 'lZf3gjBBMW1WGxYGVOGGYV9LBDzp+YAZoAp40NWiqBE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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