SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'adb50a07a9309d0915e31a6bb61182e352b2a1bdcba9442e537bdce9210bc8cd' 
  AND token = 'jsutbWuGkkZmsiuriO/fq59RxgSZjFLtvr6NV2xFlDM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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