SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8cf996a2c02f5ed0d0ca9ad3f243d258ad08162c42360cb4e5fabe43b2ab0658' 
  AND token = 'Msw0I+u6shyNJuxjbBDtBV+nKaomEKj7z+2pNxFkC1A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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