SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f467bc778b79a9652542941f60daa9815365ff761211794205621fad1f1bf4aa' 
  AND token = '0xW6DM3nsBbIvnf+Q2sAo44hnbYqKmfz1+7VlAETKnI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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