SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '046ba09595e8c8e531b14259b5f84e88d3153c8b3b5c756d06fa47a901f9f686' 
  AND token = 'nllwW4K/HxeMuyTcVgArulejMFhG+9sglDJYITWQpOQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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