SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16a500462993804937fb2153da33daa6cddeae3d388146afb8b8454f8c4d65ad' 
  AND token = 'uW/d4viPO+AlhiUhsMdRldc1xGdo9oH6Cbvz8emBm6c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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