SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8feae8bcac1fbd7c2af7eeb393220c51668ed2743de9faaef7681041b586c9fe' 
  AND token = 'AwhKkczXGclGWwmXGpDUHRxfpQ+/vO8jQdZ/ytwfmCk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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