SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccfd23bb54f8641c9a6597e9dc0f6c7e20fe9d8942f08cbf25b6dd63ff3c3a93' 
  AND token = 'lbhua4tbWGchy6UU1xvABbtMwkPmlKly5rkulanGXKA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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