SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1299cee1fcc41b0cb51d4ba2512c5747cb2a9b28798f22cbfd423f4ae12fa988' 
  AND token = 'VMW3FVrSk+gZvpUJg1HN+r3VGpma8o0t+yb45k5NizA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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