SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a10463ead68847b315ea7bf74fe176af98fb6f059d404ef0c64863bb1ecf06e3' 
  AND token = 'qZd0XdkP/w99gXBbquHHEH11JPiYsQEEe76xoFS8DpY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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