SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3198a5db21176d9d41efe891931a4ff5c07dfd2ee787a5580fecdfa76df1eceb' 
  AND token = 'HdrC9lgeKEAXoMhyAA6k+VX/0gh8WpHD7blvFXvGe04=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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