SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '92074779eb19124b058b6c5ac140d4736733a0316c855485932966e571abf239' 
  AND token = 'bvkNlCQNLY9Y+ZSq63mRKs8P/x/4rhZYf5xSpzWW1tQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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