SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89bbe393626cc39601d38bad1d18d31c8940853ba7585561472361ba4e3f6d51' 
  AND token = 'ojB4nlF/hOTuGKWEdPC7TaVJ57HKC0fZ+r5hgquiqTc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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