Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df88976ecf06a037fd838cbe658c599fd788f4589493af563701689568dab848' 
  AND token = 'Hx/v/YXfpvR2DqPRWlnzCY7bEBYWRyCRzZd9/HJDWs0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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