SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '880de9e11772160743c02360ab1767fe2eb28c639f9112ebc6d229ed8eba90ea' 
  AND token = 'uTeuNVqc1sgp/UEhw+beDq+Ng7vLyyITcW9PYl5becA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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