SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd16496c6fdcec7e250565606475cd14ef44d303dd528df180cb7aef5d912b5fc' 
  AND token = '9/fnbeXBZtfFxQD8kzt3Q9XEDo6fArkimpzUV1ppXOk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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