SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '35536e5ae98cadcf95708859ce1c78c1ca34f48ae94836299d6ffcc2c8952381' 
  AND token = 'v3plqgiIpn6c9/CbJcfQptKxqj0BjzWuYBLGtu9I+hM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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