SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48f34c89f4655b4b129efab271505452ad4c2b355292864a896c9e3578b56ddd' 
  AND token = 'vg2R5+hYm/W7+mSeViSAqX4uoC1fbvcM6JgKRVwWYiU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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