SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9cb9d2234c59c8bfdc5714859be7410f42bfd692a2f54544d84109fef28012ad' 
  AND token = 'gjzNuNdRNMCYmeJrM/LjZi6iWpWQhGexOLSV6WXZfS4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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