SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da4f92c83931180f52d213d622707e938ba05e9f36f64cf76f3e029527448abc' 
  AND token = 'uBW/SspjVS0fgziJuhbZhIkyojyfH4FaYJh0QF0CzHU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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