SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0f683f21499e94cd20df5c70536064bb249d97555ee05148ade8f830ed95fd2' 
  AND token = '9vwi8CEcpYKhWjMqR+yUVuV8b/oSLTyg2d20F5Id980=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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