SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '944b6fd429f3ccbc06cecc714c47003d9c5a1f3f5ee05efac43a3a629deac8f2' 
  AND token = 'otoHt+il89q4nJIyh1H539FZFefWDqZ9eOz185PJsJM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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