SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70f08bddb2d9442956c73692841d676bd2575fc8f58c51a6d583a6bec0e31665' 
  AND token = 'Sn7FRxX2tVlfzhUTMsH87ws/7fZd8mHhFxv38aS6CcQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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