SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1154b02af88b0068a48f4901322d5ceddce8e3596efc76b3d2eb07f94f553265' 
  AND token = 'ucjC+0XPiO4PhWMNFr7xv9pcNecJPBXW2wYNhQ+bJ0M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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