SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '972084d3f60715f003962d8a2c23bde0e5f39b23fce190d44dc2ab7455c9785f' 
  AND token = 'vJCFrlGzVcHcqVjEuTQuKv1/9K1uFINYnhtq8j0OSJk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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