SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '36b772264a7c50eb37ec9deabb779b09c23672422cd21032285a5d847dd032e3' 
  AND token = 'wEpEUQrViq7tNu0Cmn81NlKomc2v2/bi6492Q3WTYFo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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