SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'cec2ac000efb66ccabf0381632ff6fa194b33a086b5e7d140bac2f9502ddb1cf' 
  AND token = 'pAPEZFVbu/+akl/HpT0LvhdMT/xFKP7NMprkt1r35O4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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