SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2fe3d34106e58d0e6183ef0fb397f806062974aaa31c9a6b23448c77665fe7cc' 
  AND token = 'nyHzqDD3VtzRl1R9CV5N0YxaeG2LutvYwzhRgZJxo8U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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