SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '24bed8b29f671417a8fb443c35a945c78e26a0710526046174b4a70d96e95d5d' 
  AND token = '3dOQwxZ1Q1/eshays2U7BvLJGw062ctjkB/THFLRCSY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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