SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '828191ca9038d6584baaf1558d81be4c44107a85280453d2c18fb1b07e55afdf' 
  AND token = 'yL7rBngfriS9oysMAB2EyVZDFR1qORT+U20sItrflGg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00079

JSON explain

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