SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e236c8508ca5d2e6412521d2163cfb7c1bfc42d0bf7fa83989558eead1ddcdff' 
  AND token = 'UeBDHnxw1wUz+YW/GGZXT6O1IaY4+BR3giSxbmvEDCo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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