SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6bab8047edd1d24d6730c90d9758e4e52aa7f4681b138a27ccf830dfde3ecec2' 
  AND token = 'lwCZT7i31EQ8oleJgl7SvWXwG8biibo4ubJ50aJSbjg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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