SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '6951ffb4ebd0932e2ed2a677191269fea113da02ad65360457f879eb9fb09a9e' 
  AND token = 'TU/T+G4+QVr+R1QI8uXq7H2ZuKcqQ6/LEVWm6h/76NA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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