SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33cfe1cebcb9758a3f57d185f8262252e305baf6557e8d4be067febe081276a1' 
  AND token = 'VbGbmvYkIFO+qPiqTaJHFyBv9gzY119+Kdn2DX1KK14=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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