SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ef2e657959ac11c32bd73a85d0ab09a999a91185cb12c56950eeb6ce6d64430' 
  AND token = 'znDu1h3WGj/mryHQgbnEDoMGUvkjD65CEmKL+WJeND8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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