SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7043afa5c249f37455de9bd45c91d778764e9d2621c2265b7ccfb2fa99b6e3d0' 
  AND token = 'b7qtF8CfEpaVkAjvVUzjqPk0YPYKl7jL4sg+I3bjvBc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}