SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bed0a72676183b859b96f85827ce69162daf4ba0b11835b138ce4d545f44afe4' 
  AND token = 'vLPwTvqWy8VaM3TENj/JbzJcyl3CZHRm+MjgejMXalw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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