SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '91774d102eb32630d786a937e748123e1422359a28d89083859fcffd8ba34146' 
  AND token = 'Yxib5uqrOI61jiiFIny5Id9VQUkKWem814MpBhK0EkY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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