SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8b9168abc6d1d4f67ae312910a4fa626d75b50691332497df7856414ba2d585a' 
  AND token = 'Wuu7ZSFGxTsXQW3ugbt0EDs9DJwpvctjk5c0GhgcRPE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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