SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c5aa5fc77fa11adff5665c515b9a8a91e2a2f1f1c537a88210f304c57383abc' 
  AND token = 'VXrVlmEIEAy+jlaEjkpgYja6XK5EUUQkX370WzBu174=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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