SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dbcc6f10d419042de4e3ba2249f4f9992eca26685bf096138f04ba39295228ea' 
  AND token = 'eio1KVkgA+yGEYWmHKmWeFXGJN5VHt6mbXx3mk+tFyI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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