SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd06c8b033f0ec652f0c5a5ea707f0ca5cc849d9e2e17121f3a6317118192db8f' 
  AND token = 'RUC346xOL/LJw8z+JduG1BbzF+AuCowhZcYw5wioCDo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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