SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'd0845d70fc903d6aca74cdf46fbdd77be2f4353a2eb990f6bb7de49688258ea9' 
  AND token = '/+hp4tzY616/xLFc+j56PpC84udlj7eYpUKJqbiuG9c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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