SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '714d05829cb5e8be7947c75e1bae1cc7ea9b777959ff3756883fe131e06d8ae5' 
  AND token = 'vA5Gj3cKQk0g/fOirrXtLOCSQG3QotJMH9YRBLvdC90=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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