SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '569682d624160370cae307ad520c7306e3812bab1ff9842f5d70913007521779' 
  AND token = 'ri6Rk5QX6wuGYlnG2n9VZy1weOB24m5xzsMJAIuoiMw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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