SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63c90b06eb493610d68c53e5710dd166e5c558f88f19d293710829af091bfb12' 
  AND token = 'S6UrHOnYMHG3Y2ykoZKzKewDhZQFPNRK+vLwUCmiERM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00123

JSON explain

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