SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc3730be787a8abc84be49bc3036139f60ffc7a83d40625c0331ce7e4e03ddc5' 
  AND token = 'FIs8ejzTjZjeNFA6Q8lS0nr8flPBgdGOCi8reuVfZkc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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